Manufacture of web cord



Patented Apr. 11, 1939 MANUFACTURE OF WEB CORD Lon Sylvain Max Lejeune, Paris, and Emile Jean Albert Lejeune, Lille, France, assignors, by mesne assignments, to Hevaloid Corporation, Dover Del., a corporation of Delaware No Drawing. Application September 2, 1936, Serial No. 99,148. In France and Great Britain April 5, 1933 5 Claims.

Our present application has for its object the manufacture of impregnated web cord obtained by impregnation of textile elements made from assemblies of rovings which have been super- 5 twisted individually in one direction and then twisted together in the opposite direction for approximately the same number of turns, thus forming special linear elements called inversetwists which are very open to penetration by 10 liquids and whose fibers do not exert any appreciable reciprocal compression upon each other. Very good results are obtained for example with inverse twists formed of two strands of a size of 2.5, (French size) which have received an indil5 vidual twist for about 200 turns and have been assembled by an inverse twisting, also for about 200 turns.

Such special linear elements have been described in our copending application Serial No.

in 99,149, filed on September 2, 1936. Our present application relates to the use of said linear elements for manufacturing web cord, and is a continuation-in-part thereof and of our prior application Serial No. 690,760.

55 According to the present invention, a web cord, 1. e., a web which comprises substantially only warp linear elements and if desired just some I weft linear elements, is formed with a lap made from inverse twists, which are assembled parm allel to one another substantially without compression, after having been treated as follows:

Inverse twists are taken into the form of skeins and are treated without tension by means of a bath formed of an agent which produces a strong contracting and swelling of the fibres without harming the same; good results are obtained with a caustic soda lye of about 5-30 36., at a temperature of about 8-18 C., and for a time of about 5-30 minutes.

l To the bath formed of the contractingand swelling agent it may be'useful to add a wetting agent in order that the textile elements be fully wetted by the bath in which they are immersed.

As wetting agent may be employed any wetting Y agent which is commonly known for the usual treatments of textiles with liquids.

The skeins of inverse twists" are allowed to remain in the bath under the conditions de-' scribed; afterwards these skeins are removed 0 from the bath and are compressed so that the greater part of the bath may be recovered,

Preferably, after having been subjected to the treatment with the bath of contracting and swelling agent, and having been carefully washed, J the textile linear elements according to the invention are subjected to a boiling treatment, which is carried out under the conditions usual for such a treatment in the textile industry, for example with the aid of carbonate of soda lye, at the high temperature suitable for boiling. 5 The boiling treatment may be carried out as follows: the linear elements are carefully washed, and then submitted to the treatment of boiling performed under the ordinary conditions of such well-known operation, i. e., with a lye of carbo- 10 nate of soda of 3%, to which there is added a soda soap of 1.5% under a pressure of 1.5 atm. corresponding to a temperature of 113 C. for 4 hours. The percentage always is calculated with respect to the weight of dry cotton. 1 After such boiling treatment, the textile elements preferably are washed with warm water, then with cold water, and afterwards they are submitted to a treatment with hydrochloric acid or the like, then are washed and finally are carefully dried. This succession of washing treatments may be carried out as follows: the elements having been boiled are washed with warm water at 90 for about 1 hour, carefully washed with cold water, neutralized through a solution of commercial hydrochloric acid of 05 B., then again washed till the chlorides are eliminated and finally are carefully dried so that there only remains about 7% of wetness with respect to the weight of the dry cotton.

The so treated linear elements are then laid substantially parallel to one another in the form ofa lap comprising only occasional weft linear elements and so a web cord is made therefrom in the manner usually employed for manufacturing web cord in the textile industry.

It is essential to note that the succession of steps carried out consists in forming a lap with inverse twists which have already been treated and boiled, care having been taken not to exer- 40 cise a substantial tension of the inverse twists placed substantially parallel to one another during treatment;

The lap intended to form the web cord which is composed of inverse twists treated as described above, is then subjected to impregnation with an elastic or plastic substance, coagulating and drying, which operations are carried out preferably as follows:

The lap is impregnated by being immersed in 5 abath of latex, containing for example 40% of dry rubber with the vulcanising agents. The impregnation occurs preferably without vacuum or pressure being applied, in vats closed or other receptacles which are closed with a cover which y tion of the surface of the bath. After each impregnating operation, the ammonia content of the bath is brought to the required degree by adding thereto a solution of commercial ammonia.

After the impregnation, the lap of inverse twists is placed in conditions suitable for coagu lation of the rubber. To effect this, the ammonia is allowed to evaporate or is neutralized.

When the coagulation is effected, the impregnated lap is placed in such conditions that the water still contained therein evaporates for the greater part. To effect this the lap may be calendered with asusual calender so as to remove therefrom as much water as possible; afterwards the lap is dried in any suitable manner. Care should be taken that the temperature of the drying apparatus be lowered as the fabric dries.

The quantity of water remaining at that time in the lap should not exceed 4% of the weight of it is then vulcanized, preferably under a pressure of about 25/30 kg. per cmfi.

The impregnated web cord obtained according to the invention has the enormous advantage of possessing a high residual elasticity which, as is known, exists only to a small extent in the present web cord. Another advantage of the web cord according 'to the invention is its transverse compressibility which prevents chafing as in existing cords, and which, moreover, permits the compression to a reduced thickness without detriment of a larger number of laps than can be so compressed according to methods heretofore practiced. This confers upon tyres made with such laps superior qualities of elasticity and a reater strength per mmfi. Such a web cord of single or multiple lap with or without previouscompression may be used in the known manner in the manufacture of pneumatic tyres.

For the manufacture of belts the several layers of web cord according to the invention may be applied one upon the other with the strands crossed at or obliquely, and the whole vulcanised under pressure, with or without previous interposition between the different layers of web cord of a sheet of gum. The adhesion of the sheet of web cord and the layers of gum may be, if desired, improved by the application between them of a solution of rubber, incorporating or not substances suitable for ensuring vulcanisation.

What we claim is:

1. A process for the manufacture of web cord which comprises forming linear elements each composed of a plurality of rovings individually supertwisted for a certain number of turns in one direction and assembled by being twisted together in the opposite direction for approximately the same number of turns, treating the so formed linear elements without substantial tension with a bath formed of a strong contracting and swelling agent, placing the treated elements substantially parallel to one another, in the form of a formed linear elements without substantial ten- 3 which comprises forming linear elements each 7 composed of a plurality of rovings individually supertwisted for a certain number of turns in one direction and assembled by being twisted together in the opposite direction for approximately the same number of turns, placing the so formed linear elements substantially parallel to one another, in the form of a lap, treating the same without substantial tension with a bath formed of a strong contracting and swelling agent and a wetting agent, subjecting the lap to a boiling treatment, then to washing and to drying, and impregnating with elastic vulcanizable material the treated lap put in the form of web cord, then coagulating said impregnated web cord and drying it, and vulcanizing the same.

4. In the manufacture of web cord, the steps of producing a lap from inverse twists each made of rovings which have been individually supertwisted a supplemental number of turns in one direction and then assembled by twisting them together in the opposite direction for such a hum--- ber of turns'that the thus obtained linear element shows high tensile strength and elasticity and is very open throughout to penetration by liquids; treating said linear elements with a contracting and swelling agent; boiling; washing; neutralizing by an acid treatment; putting the fibrous material into the form of a lap; and impregnating the lap with rubber.

5. In the manufacture of web cord, the steps of producing a lap from inverse twists each made of rovings which have been individually supertwisted a supplemental number of turns in one direction and'then assembled by twisting them together in the opposite direction for such a number of turns that the thus obtained linear element shows high tensile strength and elasticity and is very open throughout to penetration by liquids; then treating with a contracting and! swelling agent; boiling; washing; neutralizing by an acid treatment; putting the material into the form of a lap; impregnating the lap with rubber, and vulcanizing the web cord thus formed.

' LEON SYLVAIN MAX LEJ'EUNE. EMILE JEAN ALBERT LEJEUNE. 

